Abaqus - import mesh surface

[neslon]

Hello!
I have an optimization problem to solve and I perform several abaqus analysis to calculate several objective functions.

I have a first a analysis (explicit job) with several instances (four instances) which get deformed. Then, I perform a second analysis (a static one) using the deformed configuration of one particular instance obtained at the end of the first analysis. For that purpose I use the following commands in the INP file:

*ASSEMBLY, NAME=Assembly-1
*INSTANCE, INSTANCE=PART-1, LIBRARY=previous_job
*IMPORT, STEP=2, STATE=YES, UPDATE=YES
*END INSTANCE

With the import command, nodes, elements and all elsets defined in previous_job and associated with PART-1 are also imported, but the associated surfaces aren't. In this second analysis I want to apply a pressure to the deformed surface of PART-1 and I can't pick this surface manually (in CAE for instance) because this needs to be done automatically because of the optimization process. And using import command implies dealing with orphan meshes (hexahedrons).

If I add the command *surface to the INP file of my second analysis and using the same elsets and faces associated to the surface in the first inp, or using the same datalines correspondent to the surface which are in the INP of the first analysis (which correspond to the surface and part in the undeformed state) then the deformed surface is incorrectly imported because some of the element faces don't belong anymore to the surface (in the deformed state) I really want. For a better understanding, please see this image (

http://img593.imageshack.us/img593/8018/38779374.png)

Does anyone ever faced this kind of problem?

Cheers.

 

[burningDiesel]

I don't get why your element sets and faces should change after your first analysis? Are you working with element deletion or something like that?
Like I assume you tried, you can use the *IMPORT ELSET and
*Surface, name=, type=element to recreate your surfaces.

Maybe you could try working without assemblies and parts (it's easier anyway), but like I said, the normal approach should work too.

 

[neslon]

Thanks for your reply sdebock.

I already tried *IMPORT ELSET and the result is the same.

The element sets remain the same but the faces "change their number/position" with the first analysis and I also don't get why that happens.

Is there any way to export mesh surfaces from odb ?

Because in the first analysis odb, and the end of the analysis, the surface remains well defined, obviously.

 

[IceBreakerSours]

Try working with a flat input deck.

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